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author | Nils Durner <durner@gnunet.org> | 2010-09-26 14:11:23 +0000 |
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committer | Nils Durner <durner@gnunet.org> | 2010-09-26 14:11:23 +0000 |
commit | aa51482a950a56419580587df54c17603d0390f1 (patch) | |
tree | 437974f0cc39a7919dd84b3081cdb8c70f6d0ebe /src/util/crypto_hkdf.c | |
parent | da6e4e260bdf7eb4440a9ba53bcc7e497d66181f (diff) | |
download | gnunet-aa51482a950a56419580587df54c17603d0390f1.tar.gz gnunet-aa51482a950a56419580587df54c17603d0390f1.zip |
support chunked context parameter for HKDF
Diffstat (limited to 'src/util/crypto_hkdf.c')
-rw-r--r-- | src/util/crypto_hkdf.c | 45 |
1 files changed, 36 insertions, 9 deletions
diff --git a/src/util/crypto_hkdf.c b/src/util/crypto_hkdf.c index e442aef1c..4415b7551 100644 --- a/src/util/crypto_hkdf.c +++ b/src/util/crypto_hkdf.c | |||
@@ -93,6 +93,8 @@ static void dump(char *src, void *p, unsigned int l) | |||
93 | 93 | ||
94 | /** | 94 | /** |
95 | * @brief Derive key | 95 | * @brief Derive key |
96 | * @param result buffer for the derived key, allocated by caller | ||
97 | * @param out_len desired length of the derived key | ||
96 | * @param xtr_algo hash algorithm for the extraction phase, GCRY_MD_... | 98 | * @param xtr_algo hash algorithm for the extraction phase, GCRY_MD_... |
97 | * @param prf_algo hash algorithm for the expansion phase, GCRY_MD_... | 99 | * @param prf_algo hash algorithm for the expansion phase, GCRY_MD_... |
98 | * @param xts salt | 100 | * @param xts salt |
@@ -101,15 +103,12 @@ static void dump(char *src, void *p, unsigned int l) | |||
101 | * @param skm_len length of skm | 103 | * @param skm_len length of skm |
102 | * @param ctx context info | 104 | * @param ctx context info |
103 | * @param ctx_len length of ctx | 105 | * @param ctx_len length of ctx |
104 | * @param out_len desired length of the derived key | ||
105 | * @param result buffer for the derived key, allocated by caller | ||
106 | * @return GNUNET_YES on success | 106 | * @return GNUNET_YES on success |
107 | */ | 107 | */ |
108 | int | 108 | int |
109 | GNUNET_CRYPTO_hkdf (int xtr_algo, int prf_algo, const void *xts, | 109 | GNUNET_CRYPTO_hkdf (void *result, const unsigned long long out_len, |
110 | const size_t xts_len, const void *skm, const size_t skm_len, | 110 | int xtr_algo, int prf_algo, const void *xts, const size_t xts_len, |
111 | const void *ctx, const size_t ctx_len, const unsigned long long out_len, | 111 | const void *skm, const size_t skm_len, ...) |
112 | void *result) | ||
113 | { | 112 | { |
114 | void *prk, *hc, *plain; | 113 | void *prk, *hc, *plain; |
115 | unsigned long long plain_len; | 114 | unsigned long long plain_len; |
@@ -117,6 +116,8 @@ GNUNET_CRYPTO_hkdf (int xtr_algo, int prf_algo, const void *xts, | |||
117 | unsigned int k, xtr_len; | 116 | unsigned int k, xtr_len; |
118 | int ret; | 117 | int ret; |
119 | gcry_md_hd_t xtr, prf; | 118 | gcry_md_hd_t xtr, prf; |
119 | size_t ctx_len; | ||
120 | va_list argp; | ||
120 | 121 | ||
121 | prk = plain = NULL; | 122 | prk = plain = NULL; |
122 | xtr_len = gcry_md_get_algo_dlen (xtr_algo); | 123 | xtr_len = gcry_md_get_algo_dlen (xtr_algo); |
@@ -127,6 +128,11 @@ GNUNET_CRYPTO_hkdf (int xtr_algo, int prf_algo, const void *xts, | |||
127 | if (out_len > (2 ^ 32 * k) || !xtr_algo || !prf_algo) | 128 | if (out_len > (2 ^ 32 * k) || !xtr_algo || !prf_algo) |
128 | return GNUNET_SYSERR; | 129 | return GNUNET_SYSERR; |
129 | 130 | ||
131 | va_start(argp, skm_len); | ||
132 | for (ctx_len = 0; va_arg (argp, void *);) | ||
133 | ctx_len += va_arg (argp, size_t); | ||
134 | va_end(argp); | ||
135 | |||
130 | prk = GNUNET_malloc (xtr_len); | 136 | prk = GNUNET_malloc (xtr_len); |
131 | 137 | ||
132 | memset (result, 0, out_len); | 138 | memset (result, 0, out_len); |
@@ -146,8 +152,21 @@ GNUNET_CRYPTO_hkdf (int xtr_algo, int prf_algo, const void *xts, | |||
146 | plain = GNUNET_malloc (plain_len); | 152 | plain = GNUNET_malloc (plain_len); |
147 | if (t > 0) | 153 | if (t > 0) |
148 | { | 154 | { |
149 | memcpy (plain, ctx, ctx_len); | 155 | void *ctx, *dst; |
150 | memset (plain + ctx_len, 1, 1); | 156 | |
157 | dst = plain; | ||
158 | va_start (argp, skm_len); | ||
159 | while ((ctx = va_arg (argp, void *))) | ||
160 | { | ||
161 | size_t len; | ||
162 | |||
163 | len = va_arg (argp, size_t); | ||
164 | memcpy (dst, ctx, len); | ||
165 | dst += len; | ||
166 | } | ||
167 | va_end (argp); | ||
168 | |||
169 | memset (dst, 1, 1); | ||
151 | gcry_md_reset (prf); | 170 | gcry_md_reset (prf); |
152 | #if DEBUG_HKDF | 171 | #if DEBUG_HKDF |
153 | dump("K(1)", plain, plain_len); | 172 | dump("K(1)", plain, plain_len); |
@@ -160,7 +179,15 @@ GNUNET_CRYPTO_hkdf (int xtr_algo, int prf_algo, const void *xts, | |||
160 | } | 179 | } |
161 | 180 | ||
162 | if (t > 1 || d > 0) | 181 | if (t > 1 || d > 0) |
163 | memcpy (plain + k, ctx, ctx_len); | 182 | { |
183 | void *ctx, *dst; | ||
184 | |||
185 | dst = plain + k; | ||
186 | va_start(argp, skm_len); | ||
187 | while ((ctx = va_arg (argp, void *))) | ||
188 | memcpy (dst, ctx, va_arg (argp, size_t)); | ||
189 | va_end (argp); | ||
190 | } | ||
164 | 191 | ||
165 | /* K(i+1) */ | 192 | /* K(i+1) */ |
166 | for (i = 1; i < t; i++) | 193 | for (i = 1; i < t; i++) |