ref: c1d40df49550393f3afe53fb6e6d500dfa8eb7a8
dir: /sys/src/libsec/port/decodepem.c/
#include "os.h" #include <libsec.h> #define STRLEN(s) (sizeof(s)-1) uchar* decodePEM(char *s, char *type, int *len, char **new_s) { uchar *d; char *t, *e, *tt; int n; *len = 0; /* * find the correct section of the file, stripping garbage at the beginning and end. * the data is delimited by -----BEGIN <type>-----\n and -----END <type>-----\n */ n = strlen(type); e = strchr(s, '\0'); for(t = s; t != nil && t < e; ){ tt = t; t = strchr(tt, '\n'); if(t != nil) t++; if(strncmp(tt, "-----BEGIN ", STRLEN("-----BEGIN ")) == 0 && strncmp(&tt[STRLEN("-----BEGIN ")], type, n) == 0 && strncmp(&tt[STRLEN("-----BEGIN ")+n], "-----", STRLEN("-----")) == 0 && strchr("\r\n", tt[STRLEN("-----BEGIN ")+n+STRLEN("-----")]) != nil) break; } for(tt = t; tt != nil && tt < e; tt++){ if(strncmp(tt, "-----END ", STRLEN("-----END ")) == 0 && strncmp(&tt[STRLEN("-----END ")], type, n) == 0 && strncmp(&tt[STRLEN("-----END ")+n], "-----", STRLEN("-----")) == 0 && strchr("\r\n", tt[STRLEN("-----END ")+n+STRLEN("-----")]) != nil) break; tt = strchr(tt, '\n'); if(tt == nil) break; } if(tt == nil || tt == e){ werrstr("incorrect .pem file format: bad header or trailer"); return nil; } if(new_s) *new_s = tt+1; n = ((tt - t) * 6 + 7) / 8; d = malloc(n); if(d == nil){ werrstr("out of memory"); return nil; } n = dec64(d, n, t, tt - t); if(n < 0){ free(d); werrstr("incorrect .pem file format: bad base64 encoded data"); return nil; } *len = n; return d; } PEMChain* decodepemchain(char *s, char *type) { PEMChain *first = nil, *last = nil, *chp; uchar *d; char *e; int n; e = strchr(s, '\0'); while (s < e) { d = decodePEM(s, type, &n, &s); if(d == nil) break; chp = malloc(sizeof(PEMChain)); chp->next = nil; chp->pem = d; chp->pemlen = n; if (first == nil) first = chp; else last->next = chp; last = chp; } return first; }